用C++实现2个数组的交集 和并集的函数，交集和并集按照从小到大的顺序输出。

#include <stdio.h>

// 计算数组的长度
int length(int arr[]) {
    return sizeof(arr) / sizeof(arr[0]);
}

// 升序排序数组
void sort(int arr[], int len) {
    int temp;
    for (int i = 0; i < len; i++) {
        for (int j = i + 1; j < len; j++) {
            if (arr[i] > arr[j]) {
                temp = arr[i];
                arr[i] = arr[j];
                arr[j] = temp;
            }
        }
    }
}

// 数组交集函数
void intersection(int arr1[], int len1, int arr2[], int len2) {
    sort(arr1, len1);
    sort(arr2, len2);
    int i = 0, j = 0;
    while (i < len1 && j < len2) {
        if (arr1[i] == arr2[j]) {
            printf("%d ", arr1[i]);
            i++;
            j++;
        } else if (arr1[i] < arr2[j]) {
            i++;
        } else {
            j++;
        }
    }
}

// 数组并集函数
void unionSet(int arr1[], int len1, int arr2[], int len2) {
    sort(arr1, len1);
    sort(arr2, len2);
    int i = 0, j = 0;
    while (i < len1 && j < len2) {
        if (arr1[i] == arr2[j]) {
            printf("%d ", arr1[i]);
            i++;
            j++;
        } else if (arr1[i] < arr2[j]) {
            printf("%d ", arr1[i]);
            i++;
        } else {
            printf("%d ", arr2[j]);
            j++;
        }
    }
    while (i < len1) {
        printf("%d ", arr1[i]);
        i++;
    }
    while (j < len2) {
        printf("%d ", arr2[j]);
        j++;
    }
}

int main() {
    int arr1[] = {1, 2, 3, 4, 5};
    int arr2[] = {3, 4, 5, 6, 7};
    int len1 = length(arr1);
    int len2 = length(arr2);
    printf("数组交集为：");
    intersection(arr1, len1, arr2, len2);
    printf("\n数组并集为：");
    unionSet(arr1, len1, arr2, len2);
    return 0;
}